The present invention relates to a dot matrix printer and, more particularly, to a dot matrix line printer including a print head service diagnostic and method for maximizing print actuator life.
In a shuttle matrix line printer, a single horizontal array of print wires is evenly spaced across the whole print line width. To illustrate the present invention, two exemplary printer model configurations will be described. The first model configuration is an 800 line per minute version using 33 print head modules containing two actuators each for a total of 66 actuators. In this configuration, each actuator will oscillate over 0.2 inches of dot data. The second model is a 400 line per minute version that contains 33 print head modules holding single actuators for a total of 33 actuators. In this configuration, each actuator oscillates over 0.4 inches of dot data. On each half cycle of the shuttle oscillation, the print modules will print a single horizontal dot line.
In general, a typical print actuator has a useful life of approximately one billion dots, depending on use and other factors. Because certain print actuators inherently generate more dot data by virtue of their position along the line width, it is difficult to determine when a particular print actuator is nearing the end of its useful life. Moreover, because all actuators are used over varying frequencies, it is difficult to determine which actuator should be replaced and which actuators should be left in position.
There is therefore a need to provide a dot matrix printer that is capable of monitoring the number of print actions performed by each of the print actuators to maximize output of the print actuators over their useful life regardless of their position along the actuator array.